1. Field
Embodiments of the present invention relate to a rechargeable battery.
2. Description of the Related Art
A rechargeable battery can be repeatedly charged and discharged, unlike a primary battery, which is not designed to be recharged. A small capacity rechargeable battery is used for a small portable electronic device, such as a mobile phone, a laptop computer, or a camcorder. A large capacity rechargeable battery is used as a power source for driving a motor, such as for a hybrid electric vehicle.
A high power rechargeable battery using a high energy density non-aqueous electrolyte has been developed, and such a high power rechargeable battery is formed by coupling a plurality of unit cells in series in order to drive a motor of a machine or equipment, for example an electric vehicle that requires a large amount of electric power.
A unit cell of the rechargeable battery is formed with a cylindrical shape or a rectangular shape. A rectangular rechargeable battery includes an electrode assembly in which a positive electrode and a negative electrode are positioned with a separator located therebetween, a case that houses the electrode assembly, and a cap plate that closes and seals the case and that has a terminal hole. A terminal is inserted into the terminal hole, is electrically connected to the electrode assembly, and protrudes to the outside of the case.
If excessive heat occurs at the inside thereof due to charge and discharge operations, or if an internal pressure rises due to decomposition of an electrolyte solution, such a rechargeable battery may explode or ignite. It is difficult for a rectangular rechargeable battery to have a structure for interrupting or discharging a current upon overcharge due to particularity of its terminal structure, compared with a cylindrical battery.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the embodiments disclosed herein and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.